I've noticed that I skipped over this title when I did my first round of reviewing, and I think the reason for that is because this film had no sound. Judging by the images, its ok, with the first half much more interesting then the second. The first half has great images of people turning on radios and people broadcasting. The second half is more technical blah.

The film is an accurate depiction of radio network interconnections, many of the same transmission techniques were used by radio networks such as NPR until 1980 when analog satellite interconnections rendered the land-line connections obsolete. Commercial networks followed with their own satellite interconnections.
It's funny, but modern radio networks still use the same functional layout: audio switching, accurate timing for the downstream stations, and now thye nets can send text and metadata to enhance the listener's experience.
We owe the radio pioneers depected in the file a "thank you" for developing these highly technical schemes.

Untill I've been able to watch this, I'll leave you with the Brinkley Act:

http://en.wikipedia.org/wiki/Brinkley_Act

-uniQ

This film is about how telephones play a role in spreading radio network broadcasts in the early 1930s. Unfortunately, this print is missing the soundtrack, but we are left with a lot of great imagery.

The film seems to explain how the sound transmitted over the telephone lines is optimized for the standard range of an orchestra and the broadcast over the radio. To illustrate this point, there is quite bit of period animation showing how different instruments compare to the tones of a piano and how that relates to sound frequencies. There is also a number of maps showing the different radiotelephone repeaters that are used, perhaps using NBC as an example (because of the color coding of the networks; Red, Blue, Orange, Purple, Brown). Perhaps the best shot is three minature instruments running along a musical staff that becomes telephone wires.

The film is also full of old time shot transitions; iris in and out, fan wipes, etc. Finally, a bunch of shots of 1930s era radio and telephone equipment, including performers before the microphone. I think one of the performers towards the end of the film is Baby Snooks, famous radio star from the era. The film ends rather abruptly, but it's not clear if there is a second part, or the end just got cut off.

Lots of great footage, but it's a shame that the soundtrack is missing, or this would make an even better document.

This appears to be the first part of a short on network broadcasting of radio from the mid to late 30's. Many scenes of listeners with early radios, plus technicians with period radio broadcast gear.